hematopoietic lineage cell-specific protein; hematopoietic cell-specific LYN substrate 1; LckBP1; p75 (HCLS1, HS1)

Function

• substrate of the antigen receptor-coupled tyrosine kinase
• plays a role in antigen receptor signaling for both clonal expansion & deletion in lymphoid cells
• may also be involved in regulation of gene expression
• phosphorylated by LYN; rapidly after cross-linking of surface IgM on B-cells
• associates with the SH2 domain & SH3 domain of LCK
• binding to the LCK SH3 domain occurs constitutively, while binding to the LCK SH2 domain occurs only upon TCR stimulation
• a similar binding pattern is observed with LYN, but not with FYN in which the FYN SH2 region associates upon TCR stimulation but the FYN SH3 region does not associate regardless of TCR stimulation
• directly associates with HAX1, through binding to its C-terminal region
• interacts with HS1BP3

Structure

• contains 4 cortactin repeats
• contains 1 SH3 domain

Compartment

• peripheral membrane protein
• cytoplasm (probable)
• mitochondrion (probable)

Expression

• expressed only in tissues & cells of hematopoietic origin
• expressed in early stage of myeloid & erythroid differentiation

More general terms

• phosphoprotein

Database

• Entrez gene: http://www.ncbi.nlm.nih.gov/sites/entrez?db=gene&cmd=Retrieve&dopt=Graphics&list_uids=3059
• Kegg: http://www.genome.jp/dbget-bin/www_bget?hsa:3059
• OMIM: https://mirror.omim.org/entry/601306
• UniProt: http://www.uniprot.org/uniprot/P14317.html